Acta Chimica Sinica ›› 2004, Vol. 62 ›› Issue (24): 2415-2420. Previous Articles     Next Articles


邢军1,2, 谭志诚1, 邸友莹1, 孙晓红3, 孙立贤1, 张涛1   

  1. 1. 中国科学院大连化学物理研究所, 热化学实验室, 大连, 116023;
    2. 大连大学化学与化学工程系, 大连, 116622;
    3. 西北大学化学研究所, 西安, 710069
  • 收稿日期:2004-01-30 修回日期:2004-09-11 出版日期:2004-12-28 发布日期:2014-02-17
  • 通讯作者: 谭志诚,
  • 基金资助:

Thermodynamic Study of Methyl N-(4,6-Dimethoxypyrimidin-2-yl)carbamate

XING Jun1,2, TAN Zhi-Cheng1, DI You-Ying1, SUN Xiao-Hong3, SUN Li-Xian1, ZHANG Tao1   

  1. 1. Thermochemistry Laboratory, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023;
    2. Department of Chemistry and Chemical Engineering, Dalian University, Dalian 116622;
    3. Department of Chemistry, Northwest University, Xi'an 710069
  • Received:2004-01-30 Revised:2004-09-11 Online:2004-12-28 Published:2014-02-17

The low-temperature heat capacities of the methyl N-(4,6-dimethoxypyrimidin-2-yl)carbamate were measured with an automatic adiabatic calorimeter over the temperature range from 80 to 380 K. A solid-liquid phase transition was observed at Tm=(357.201?0.080) K, and the molar enthalpy and entropy of fusion were determined to be (26.289?0.029) kJ·mol-1 and (73.597?0.070) J·K-1 ·mol-1, respectively. The purity, the real melting point (T1) and the ideal melting point without any impurity or with absolute purity (To) of the compound under investigation were determined to be 99.10 mol%, 357.085 and 357.449 K, respectively, through fractional melting method. The thermodynamic functions relative to the reference temperature 298.15 K were derived based on the heat capacity measurements. Further research on thermodynamic properties of this compound was carried out by means of TG-DTG and DSC techniques. The boiling point and the enthalpy of evaporation for the compound were determined to be 488.06 K and 81.73 kJ·mol-1, respectively.

Key words: methyl N-(4,6-dimethoxypyrimidin-2-yl)carbamate, adiabatic calorimetry, low-temperature heat capacity, thermodynamic function, TG-DTG, DSC